Miele TOUCHTRONIC T 9802 Operating And Installation Instructions page 40

Installation
Example
Rigid pipe
A
B
C
D
E
Total duct
length
The total duct length is less than 33 feet (10 m), so a duct diameter of 4" (100 mm)
with adapter is sufficient.
36
Wall duct with louvered
wall vent
90° bend
20" (0.5 m) rigid pipe
90° bend
left / right vent opening
Duct length
ft
12' 5"
2' 4"
1' 7"
2' 4"
3' 3"
18' 8"
Duct length
m
3.8 m
0.7 m
0.5 m
0.7 m
1.0 m
5.7 m